import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    static long largestValue(int[] A) {
       int max=A[0];
        int theind=0;
       for(int i=1;i<A.length;i++){
          if(A[i]>max){
              max=A[i];
              theind=i;
          }
           
       }
       if(A[theind]==A.length-1){
           long sum =0;
           long sum1 =(A[theind]*A[theind])+(A[theind]*A[theind]);
           return sum;
       }
      int g=A.length-theind;
     for(int j=theind;j<g;j++){
       long sum=0;
         int l=0;
         l= (A[j]*A[theind]);
         sum+=l;
         return sum;
         
     }
    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int[] A = new int[n];
        for(int A_i = 0; A_i < n; A_i++){
            A[A_i] = in.nextInt();
        }
        long result = largestValue(A);
        System.out.println(result);
        in.close();
    }
}